Electric-snap-switch cover.



No. 660,633. Patented 00L 30, |900.

M. (UETT.

ELECTRIC SNAP SWITCH COVER.

(Application led June 27, 1900.)

UNiTnD STATES PATENT OFFICE.

MONROE GUETT, OF HARTFORD, CONNECTICUT, ASSIGNOR TO THE HART & HEGEMAN MANUFACTURING COMPANY,-OF SAME PLACE.

ELECTRIC-SNAP-SWITCH COVER.

SPECIFICATION forming part of Letters Patent No. 660.633. dated October 30, 1900. Application led Tulle 27| 1900. SeriahNo. 21,842. (No model.)

To all whom, it may con/cern:

Be it known that I, MONROE GUETT, a citizen of the United States, residing at Hartford, inthe county of Hartford and State of `Connecticut, have invented certain new and usef ul Improvements in Electric-Snap-Switch Covers, of which the following is a specification.

This invention relates to those cu p-shaped covers which are placed upon the bases of rotary snap-switches for inclosingr the mechanisms.

The objectof the invention is. to provide a simple, inexpensive, easily-formed cover which has such characteristics as to eliminate all liability of short-circuiting current bythe cover when the cover' is upon or is being placed upon or being removed from the base.

The embodiment of the invention that is illustrated in the accompanyingdrawings cousists of a cup-shaped exterior shell that is stam ped to shape from sheet metal and a cupshaped interior shell that is pressed from a single piece of peculiarly-blanked insulatingpaper.

Figure l of the views shows a plan of the blank of insulating-paper from which the interior shell is formed. Fig. 2 isadiametrical section of the interior shell that is pressed from the blank. Fig. 3 is a view looking into the interior shell. Fig. 4 is a diametrical section ofthe cover composed of the combined exterior metallic and interior insulating-shells,

and Fig. 5 is aview looking into the completed cover.

The exterior shell of the cover is stamped from a single piece of thin sheet metal by a common punch and die, so as to form the circular top portion l and the annular side portion 2. A perforation 3 is madethrough the center of the top portion of the metallic shell. The blank 4 is cut from a sheet of paper or press board having the requisite insulating qualities and mechanical strength and pliability, with radially-projecting tongues 5 and acentral perforation 6, that is slightlysmaller in diameter than the perforation 3 through the metal shell. These tongues are formed by removing triangular pieces of material from between them, so that the opposite'side edges of each tongue are parallel. The outer edge of each tongue is a straight line extending at right angles to the side edges, and the apexes of the triangular openings '7, between 'the tongues, are in a circle having the diameter of the inside of the top of the cover. Each tongue is slightly Vlonger than the width of the annular side portion 2 of the metallic shell. The blank thus cut from insulatingpaper is laid upon the edges of the annular side portion of the metallic shell and then by the plunger of a suitable press forced down into the metallic shell until the circular portion 8 at the centerlies against the inside of the circular top portion 1 of the metallic shell. 65

When the insulating-blank is forced into the metallic shell, the tongues bend at right anz gles and their side edges meet, so that a cupshaped shell is formed of the insulating material inside of the metallic shell.

The perforation through the top of the cover is provided for the switch-spindle, and the perforation through the metallic shell being slightly larger than the perforation through the insulating-shell it is impossible for the metallic shell to come into contact with the switch-spindle. As the tongues are somewhat longer than the width of the annular portion of the metallic shell the edge of the inner shell extends beyond the edge of 8c the metallic shell, making itimpossible for the metallic shell to be brought into contact with any of the switch parts when the cover is being placed upon or being removed from the base.

A cover formed according to this invention may be made with a thin exterior metallic shell which is cheaply manufactured and is capable of a high polish and decorative ornamentation, which thin metallic shell is strengthened by the interior shell, which has such rigidity that when forced into place it remains in position without the employment of any adhesive substance. Not only can the metallic shells of the covers formed in this manner be made of thin metal, but they are completely insulated, so that there is no danger of short-circuiting current through the switch parts by accidental contact when the cover is being placed in or being removed from position or by the gathering of moisture inside of the cover or by the contact with the IOO inside of the cover of the ends of the linewires.

I claim as my invention- `1. A cover for a rotary snap-switch ,consisting of an exterior metallic shell having` a circular top portion with a central perforation and an annular side portion, and an interior shell formed of sheet insulatinganaterial with a circular top portion having a central perforation and an annular side portion formed of integral tongues projectingfroin the central portion, the side Iedges of each tongue being parallel and the end edge of each tongue being at right angles with the side edges, substantially as specified.

2. A cover for arotary snap-switch consisting of an exterior metallic shell havingacircular top portion with a central perforation and. an annular side portieri, and an interior insulating-shell having a circular top portion with a. central perforation that is smaller in d ameter than the central perforation through lhe'circular top portion of tl-evmetallic shell, and an annular portion vthat is wider than the annular portion of. the metallic shell, sub stantially as specified.

MONROE GUETT.

Witnesses:

H. R. WILLIAMS, V. R. HoLCoMB. 

